Changes in self-reported incidence of nocturnal bruxism in college students: 1966-2002.

The frequencies of self-reported nocturnal bruxism in four large samples of college students were compared to assess change in the incidence of this disorder since 1966. Analysis showed incidence of nocturnal bruxism increased from 5.1% to 22.5% over this period. However, the increase from our 1989 sample was not statistically significant.